This invention relates to a freezing refrigerator of a direct cooling type and, more particularly, a freezing refrigerator with a defroster.
Generally, a home-used refrigerator is provided with a freezing chamber and a cold chamber, and is classified into a direct cooling type refrigerator and an indirect cooling type refrigerator. The indirect cooling type refrigerator circulates a cooling air through the freezing chamber and the freezing cooler to indirectly cool the freezing chamber. The direct cooling type refrigerator employs a substantially rectangular box made of good thermally conducting material for the freezing chamber with a freezing cooler disposed therearound to directly uniformly cool most of the entire interior of the freezing chamber. The direct type refrigerator directly cools the freezing chamber so that, during the cooling operation, frost is attached to almost the entire inner surface of the freezing chamber. The attached frost adiabatically acts to reduce the cooling effect.
It is the practice to defrost the frost-attached freezing chamber in a manner that food in the freezing chamber is taken out and the inside of the freezing chamber is heated to room temperature, after stopping the freezing operation. This defrosting method probably thaws the frozen food and needs a troublesome work to stop the freezing operation and take out the frozen food from the freezing chamber. Coping with this problem, there is proposed a refrigerator with a heater for defroster which is disposed, together with the freezing cooler, around the freezing chamber and is supplied with power when necessary. This method indeed defrosts the frost attached onto the inner wall of the freezing chamber reliably and swiftly; however, there is a high possibility that the frozen food is defrozen. For this reason, the frozen food must temporarily be taken out from the freezing chamber for defrosting operation.